Partitioned Enclose

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Partitioned Enclose () is a dyadic function which splits its right argument into differently sized pieces as determined by the left argument.

Basic functionality

In the simplest case, and on a vector right argument, the corresponding element in the left argument indicates where divisions begin:

      1 0 1 0 0 0 0⊂'HiEarth'

Non-Boolean left argument

Almost all dialects restrict the left argument to provide only the above functionality. However, the left argument can be interpreted as a count of how many partitions begin with a particular position:

      2 0 3 0 0 0 0⊂'HiEarth'

Short left argument

The dialects that support this extension also allow omission of trailing zeros, which is useful if the partitioning vector is generated by where's inverse:

      ⍸⍣¯1⊢1 1 3 3 3
2 0 3
      2 0 3⊂'HiEarth'

Long left argument

Additional trailing empty divisions are created by adding an additional division count corresponding to the position beyond the end of the right argument:

      1 0 1 0 0 0 0 1⊂'HiEarth'

Split into lengths

This above extensions allow a simple definition of a split-into-lengths function:

Try it online!

      Split←{⍵ ⊂⍨ ⍸⍣¯1 +\ ¯1↓1,⍺}
      3 3 4 Split 'HowAreYou?'

See also

External links



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